Optical properties of an open three-level atomic system via coherent and incoherent fields

In this paper, coherent and incoherent control of optical properties of open ladder- type three-level atomic system is investigated. It is shown that in the presence of spontaneously generated coherence (SGC) and incoherent pumping filed, group velocity, absorption and dispersion of the probe field can be controlled by adjusting the ratio between atomic injection and exit rates. Also, the bistabal behaviors of the system are discussed. It is shown that the ratio between atomic injections and exit rate can influence the bistabal threshold intensity and related hysteresis loop. More interestingly, it is found that SGC and incoherent pumping field effects have a central role for distinguishing between open and closed system.